r_sam_14
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MFC
We use ON_WM_PAINT() macro to invoke the handler OnPaint(),similarly we use OnDraw(CDC *pDC) which the MFC frame work calls , what is the basic difference between these to calls ?
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I am fine and hope same to u. I will try my best to answer ur queries and hope u will get more clear figure.
WM_PAINT is a message .So frame work has to send it to the control or parent. For that we need to map the message and thus ON_WM_PAINT message come to existance. But for OnDraw () as I told u earlier also it is not message like WM_PAINT and tell u when it is called.
It is a virtual function and class or object has to overide this function to draw itself. So whenever document want to print or print priview it ..It just calls OnDraw() with specfic CDC Object and and draw itself.
Now I think u r doubt is more clear..
Regards keshav..